282 HYMENOPTERA. 



quence of the errors discovered in those of St. Fargeau in the 

 ' Histoire naturelle des Insectes '; after a careful microscopic 

 examination of several individuals of this genus, only rudiment- 

 ary palpi or a small tubercle has been found in the maxillae ; 

 St. Fargeau gives six joints in his characters. The genera Me- 

 soplia, Hopliphora and Mesonychium of St. Fargeau are stated 

 by that author to agree with the genus Mesocheira in the cha- 

 racter of the oral organs ; on a careful examination of those 

 parts they are found to differ very widely, and the difference in 

 the number of spines which arm the large calcaria of the inter- 

 mediate tibiae cannot be considered as affording anything beyond 

 specific distinctions. 



1. MESOCHEIRA BICOLOR. B.M. 



Melecta bicolor, Fabr. Syst. Piez. p. 386. 3. 



Mesocheira bicolor, St. Fare/. fy Serv. Ency, Meth. x. 106. 



Crocisa bicolor, Jurine, Hym. p. 241. 



In this species the scutellum is produced over the base of the 

 abdomen and deeply notched. 



Hab. Brazil; Cayenne. 



2. MESOCHEIRA SERICEUS. 



Mesocheira sericeus, Guer. Icon. Reg. Anim. p. 456. 

 Hab. Rio Janeiro. 



3. MESOCHEIRA ASTERIA. 



Female. Length 5 lines. Head and thorax black, the face 

 covered with silvery- white pubescence, a line of similar pubes- 

 cence passes along the margin of the vertex and down the outer 

 margin of the eyes ; the flagellum rufo-piceous beneath ; the base 

 of the scape ferruginous in front. Thorax, the tubercles and 

 tegulae in front rufo-piceous ; the scutellum bituberculate ; a 

 line on the collar continued round the tubercles, and the margins 

 of the scutellum bordered with white pubescence ; at the sides of 

 the metathorax a tuft of white pubescence ; the wings hyaline at 

 their base, and having a fuscous cloud at their apical margins, 

 the nervures black ; the spurs at the apex of the intermediate 

 tibia3 elongate, filiform, slightly bent, and notched at the apex, 

 one side of the notch produced into a sharp spine, the other side 

 bidenticulate ; the spines on the posterior tibiae finely serrated 

 within. Abdomen conical, of a beautiful bright green, having a 

 silken texture ; the sides adorned with silvery-white markings ; 

 beneath testaceous, having spots of purple colouring, the sides of 



